/*
    This file is part of the substandard lisp implementation of Standard Lisp
    Copyright (C) 2011 Nicky Nickell

    substandard lisp is free software: you can redistribute it and/or modify
    it under the terms of the GNU General Public License as published by
    the Free Software Foundation, either version 3 of the License, or
    (at your option) any later version.

    This program is distributed in the hope that it will be useful,
    but WITHOUT ANY WARRANTY; without even the implied warranty of
    MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
    GNU General Public License for more details.

    You should have received a copy of the GNU General Public License
    along with this program.  If not, see <http://www.gnu.org/licenses/>.
*/

(dm if (u)
  (let ((test (second u))
         (positive (third u))
         (negative (cdddr u)))
    `(cond (,test ,positive) (t (progn ,@negative)))))

/*---
name: if

doc: |
  explaining what if is / how it is used!

tests: |
  (if T 1) -> 1
  (if NIL 1) -> NIL
  (if T 1 2) -> 1
  (if NIL 1 2) -> 2
  (if t 1 2 3 4) -> 1
  (if NIL 1 2 3 4) -> 4
...*/
